Work in this laboratory has focused on the regulation of mammalian phosphatidylcholine metabolism, which is regulated by the enzymes choline kinase and CTP: cholinephosphate cytidylyltransferase (CCT). We hypothesize that cellular choline kinase activity is modulated by the selective expression of choline kinase isozymes in certain cells and in response to certain signals. We are isolating, expressing, and analyzing the expression patterns of choline kinase isoforms from mammals and the nematode, C. elegans. In addition, we are studying the regulation of CCT activity by phosphorylation and lipids, and have been studying the catalytic mechanism of this enzyme. We use recombinant DNA techniques for all these studies, and require the use of the GCG data base and sequence analysis software to continue them.